1. Field of the Invention
The present invention relates to a portable, self-contained heater/cooler system.
2. Related Art
A thermal electric module is a well-known interchangeable heating/cooling element. The thermal electric module typically has two heat transferring plates, separated by semi-conducting material, that transfer heat from one plate to the other when a current is applied to the semi-conducting material. Whether one of the two plates acts as either a heating plate or a cooling plate depends on the direction of the current through the thermal electric module. For example, when the current flows in a first direction through the thermal electric module, heat transfers from the first plate to the second plate so that the second plate gets hot while the first plate gets cold. When the current is reversed and flows in an opposite direction, heat transfers from the second plate to the first plate so that the first plate gets hot while the second plate gets cold.
Many conventional heating/cooling systems use thermal electric modules in combination with fans for air cooling/heating operations. In these systems, however, the speeds of the fans and the rates of the current flows through the thermal electric modules are fixed. With fixed fan speeds and fixed rates of current flow through the thermal electric module, these systems do not adapt to varying system conditions and are inefficient in achieving desired system conditions.
Therefore, there is a need for a portable self-contained heater/cooler system that adjusts various system parameters according to varying system conditions to reach desired system parameters in efficient ways.
In an exemplary embodiment of the present invention, a portable heater/cooler system, is provided, which comprises a thermal electric module conducting a current through the module; a heater/cooler cavity coupled to the thermal electric module; a variable speed fan for blowing air over the thermal electric module and into the cavity; a first temperature sensor coupled to the thermal electric module for measuring the temperature of the module; a second temperature sensor coupled to the heater/cooler cavity for measuring the temperature in the cavity; and a microprocessor for adjusting a speed of the fan and the current flow through the thermal electric module as a function of the measured temperatures of the thermal electric module and the cavity.
In another exemplary embodiment, the heater/cooler system comprises: a housing defining a cavity; a thermal electric module in communication with the cavity; an adjustable speed fan, the fan being arranged to blow air across the thermal electric module and into the cavity; a power supply supplying power to the fan and to the thermal electric module; a first temperature sensor arranged to measure a temperature of the thermal electric module; a second temperature sensor arranged to measure a temperature in the cavity; and a microprocessor receiving the measured temperatures of the thermal electric module and the cavity and controlling the power supplied to the fan and the power supplied to the thermal electric module based on at least one of the temperature in the cavity, the temperature of the thermal electric module, and a current flowing through the thermal electric module.
According to another aspect of the invention, there is provided a method for controlling a temperature in a cavity of a heater/cooler comprising: providing a module driving signal to a thermal electric module; providing a fan driving signal to an adjustable speed fan; blowing air with the fan through the thermal electric module and into the cavity; detecting a temperature of the thermal electric module; detecting a temperature in the cavity; adjusting the module driving signal based on the temperature in the cavity; adjusting the fan driving signal based on the temperature of the thermal electric module.
Further features and advantages of the invention, as well as the structure and operation of various embodiments of the invention, are described in detail below with reference to the accompanying drawings.